A dog sometimes picks up what appears to be a really yucky morsel. He may carry it around in his mouth or even eat it! The thought that it must taste awful leaps to mind. You know that the tidbit just can’t taste good. The dog, however, seems to find it yummy.
The sense of taste in a dog has a long history. It was important for canine ancestors for survival as it signaled if food was safe to eat. Our modern day pups follow the same rule of thumb. Fare that tastes good is considered safe to gobble while a scrap that tastes bad may be harmful and should be left alone. Our opinion of what tastes good may differ from that of a dog.
Humans have approximately 9,000 taste buds while dogs have about 1,700 and cats only 470. Obviously, our sense of taste is much keener than that of dogs and cats. According to the American Kennel Club, dogs have 300 million scent receptors that give them an exceptional sense of smell. The scent receptors capture molecules that tell a dog how a food will taste before he ever wraps his lips around it.
A dog’s gustatory sense or sense of taste is present at birth but takes several weeks to fully develop. The taste buds of dogs and people perceive the flavors of different foods. Taste buds are located in little bumps called papillae on the surface of the tongue. There are also some taste buds on the soft part of the roof of the mouth and the back part of the mouth were the throat begins. Each papilla houses three to five taste buds and each taste bud contains 10 to 50 sensory cells.
The sensory cells in humans and dogs are tuned to recognize specific chemical groups released from food. When activated, a receptor sends a message to the brain that interprets the information as a recognizable taste.
Dogs, cats and other carnivores are very different from us as they have taste buds tuned for water. These are lacking in humans. We can feel water as a fluid as it passes through our mouth. We can taste flavored additives, but we cannot actually taste water. Carnivore water taste buds are located at the tip of the tongue, which is the part that curls to lap water.
Taste buds that sense sour, bitter, sweet, or salty foods are common to dogs and people. The tastes are the same, but the appreciation for each is different in humans and dogs.
How the taste of salt is appreciated is a case in point. We and many other mammals have a strong taste response to salt. We actually crave it or seek it out since it is needed to balance our diets which are high in veggies and grains that contain little salt. That’s why pretzels, popcorn, chips, and other salty snack foods are so popular.
Dogs are omnivores. In the wild, about 80 percent of a dog’s diet consists or meat. Meat has a high sodium content, so wild canine ancestors never developed salt cravings. Sodium or salt was a normal part of their diet. Our domesticated pups can taste salt but like their ancestors do not have a strong need or desire for it in their diet.
It is necessary for a wild dog to supplement his diet with plants. The sweet taste buds of dogs respond to many fruits and veggies that contain a sweet-tasting chemical called furaneol. Most dogs do like sweets. Cats, by the way, do not taste sweet.
Dogs don’t care for sour-tasting foods like lemons, but they really don’t like bitter-tasting substances. Some companies have capitalized on this fact and created bitter-tasting products to discourage pups from chewing your chair legs or shoes. Active ingredients range from simply bitter flavors like oregano to very bitter hot and spicy things like capsaicin. They are harmless but are not flavors dogs like.
The products may or may not safeguard your off limit items. If a dog takes a quick lick or hasty gulp of the object, it may be so short lived in his mouth that the bitter taste buds aren’t activated. The sprays and gels work better on objects a pup spends a lot of time chewing.
The next time you wrinkle your nose in disgust at something your dog puts in his mouth, remember he is not tasting it as you would. He has far fewer taste buds. His sense of taste simply is not as discriminating as yours.
C. Sue Furman, Ph.D. spent 40 years at several major universities including the University of Maryland, School of Medicine and Colorado State University, College of Veterinary Medicine and Biological Sciences teaching future physicians and veterinarians and conducting research involving nerve and muscle. Learn more about Dr. C. Sue Furman here.